Ecology Expert: Man-Made Wetlands Fall Short Of Natural Ones

Despite statewide efforts to restore and replace wetlands that are filled in or disturbed during development projects, those man-made solutions don't match up to the real thing, one ecology expert says.

"The attempt to compare something that humans created or restored to something natural has shown a shortfall in the outcome," said Joy Zedler, professor emerita of botany and restoration ecology at the University of Wisconsin-Madison. "Some functions and some magnitude of functions fall short of what would be present in the same kind of wetland in the same place if it were left in its natural condition."

Wetlands are locations saturated by salt or fresh water or a combination of both, according to the World Wildlife Fund. The conservation organization says examples of this include marshes, ponds, edges of lakes and oceans, deltas or frequently-flooded low-lying areas.

"We've got a type of ecosystem that is in the minority of habitats and areas producing some huge proportion of services for humanity," Zedler said. "And why would anybody ever think of destroying that natural capability? It's beyond me."

Ecologists and environmental groups are stepping in to protect wetlands, particularly after a series of developments have been proposed across the state that would affect them. One of the well-publicized developments includes Foxconn Technology Group's plan to fill 16 acres of wetlands in an area selected to house a multi-billion dollar plant to manufacture LCD screens.

Foxconn has said that for every acre it fills, two acres of wetland will be created through a $2 million payment to the Wisconsin Wetland Conservation Trust.

In another case, the state's granting of a permit to the Kohler Company to build a golf course along Lake Michigan — part of which would be on Kohler-Andrae State Park — has sparked a legal hearing in Sheboygan.

A different plan in Michigan has come under scrutiny after a permit was issued to allow Canadian company Aquila Resources to mine gold, zinc and other metals near the Michigan-Wisconsin border.

Map showing "wetland gems" or "high quality habitats," according to the Wisconsin Wetlands Association. Courtesy of the Wisconsin Wetlands Association.

The U.S. Environmental Protection Agency refers to wetlands as a connection between land and water, or "transition zones."

Wetlands are home to thousands of species such as water lilies, frogs, snakes, turtles, waterfowl, fish and mammals, the agency reports, also noting their importance to resting migratory birds. The Wisconsin Department of Natural Resources states that endangered floral species often live in wetlands.

Wetlands also slow down floodwaters, which the EPA said reduces property damage. Additionally, wetlands help mitigate the amount of nutrients, sediment and pollutants that might otherwise drain into larger bodies of water.

Their benefits weren't always known, Zedler said, noting that up until the 1980s, wetlands were referred to as wastelands and often drained or covered up.

"Since then we have learned that it's like shooting ourselves in the foot to drain and get rid of wetlands or seriously modify them because they do so much for us," she said.

Wetland destruction has numerous causes, including being filled in and being drained, the latter of which impact much of Wisconsin's wetlands, Zedler said.

About 15 percent of the state is wetland, Wisconsin Wetlands Association reports, though Wisconsin has throughout its history lost more than 40 percent of its original wetland area (about 10 million acres). Zedler said the state's surrounding neighbors including Iowa, Illinois, Indiana and Ohio have lost 85 percent of theirs.

"Every square inch of wetland deserves protection because of its enormous functional value," Zedler said. "We would be smart to protect every square inch."

For wetlands that have been disrupted, Zedler noted it can be a challenge to reverse course.

The first thing to do is figure out what was done to the wetland and what factors changed it, something Zedler said is difficult to do.

Wetlands that have been drained can sometimes be restored by inserting blockages to the drainage ditch to prevent water from flowing away.

More complicated situations arise when installed perforated pipes and drain tiles direct the flow of water to a ditch elsewhere.

"At one point, the upper Midwest had over 1,100 factories making drain tiles," she said. "That give us some idea of the magnitude of the wetland drainage operation that took place as the upper Midwest was being colonized."

While wetlands can be difficult to create, smaller ones can be built in backyards, according to the U.S. Department of Agriculture, which advises homeowners to start with a low spot in the yard or drainage area with clay soils.

"Establishing a wetland in your yard may be as simple as planting wetland plants in an existing wet area, or it may require the same effort needed to install a backyard pond," the USDA states.

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